Pumps



United States Patent 3,137,240 PUMPS Russell G. Hunt, 1308s. Shelley,Santa Ana, Calif. Filed July 17, 1961, Ser. No. 124,692 2 Claims. (Cl.103-149) This invention pertains to new and improved pumps. Morespecifically this invention pertains to what may be termed tube pumpsinasmuch as each of such pumps utilizes an elastomeric tube inconjunction with means for compressing this tube in order to achieve apumping action. Many different specific designs for pumps of thisgeneralized type have been created in the past. As a general rule suchprior tube pumps have utilized a rotor 1n order to compress the tube inorder to achieve a pumping action. Tube pumps of the broad categoryindicated in this paragraph are commonly used in order to create avacuum for various purposes in chemical fields inasmuch as with pumps ofthis type there is no danger of contamination of the material within thetube and inasmuch as most elastomeric tubes are relatively inert withrespect to many common types of chemical solutions.

Although tube pumps as the term is used in the preceding paragraph arewell known, there is a definite need for improvement in pumps of thiscategory. To a large extent this need is for pumps of the categorydescribed which are relatively simple to construct, easy to maintain,and which are capable of operating satisfactorily over prolonged periodswhenever this is desired, and which can be used either intermittently orcontinuously as required for any specific operation. A broad object ofthe present invention is to provide pumps that satisfy this need.

A more specific object of this invention is to provide new and improvedpumps of a tube pump category as explained in the preceding which can beoperated satisfactorily for prolonged periods at a comparatively nominalcost with a minimum of maintenance. Other objects of this invention areto provide tube' pumps as described which may be conveniently used inorder to handle various corrosive liquids such as chlorine solutionswithout difiiculty, and which are capable of being employed as suctionor vacuum pumps during such use. A related object of this invention isto provide new and improved pumps of the type indicated which arerelatively inexpensive to manufacture.

These and various other objects of this invention as well as manyspecific advantages of it will be more fully apparent from a detailedconsideration of the remainder of this description, the appended claimsand the accompanying drawing in which:

FIG. 1 is a perspective view of a pump of this invention;

FIG. 2 is a cross-sectional view taken at line 22 of FIG. 1;

3,137,240 Patented June 16, 1964 shaped cavity. With a pump of thisinvention an elastomeric or flexible tube extends around the peripheryof the cavity and means are attached to the shaft so as to periodicallycompress the portions of the tube within the interior of the cavityitself. The pumps of the present invention also include a number ofspecific features which are utilized in this generalized construction soas to achieve the preceding objectives of the present invention.

These features are best explained by referring directly to theaccompanying drawing in which a pump 10 of this invention isillustrated. This pump 10 includes a horizontal base 12 which carries avertical, upstanding wall 14. On the back side 16 of this wall 14 asmall speed reducing gear box 18 is secured to the wall 14 by means ofscrews 20. Other screws 20 are used to hold a small electric motor 22upon the gear box 18. The shaft 24 forming a part of this motor 22carries a small fan blade 26; this shaft 24 extends into the gearbox 18so as to supply power to this gear box. Power is taken from the gear boxby means of a shaft 30 extending through a centrally located hole 32 inthe wall 14 so as to terminate on the front side 34 of this wall 14.

Preferably a small housing 36 for protective purposes is mounted uponthe back side 16 of the wall 14 so as to surround the gear box 18and'the motor 22. This housing 36 may conveniently be provided withventilation holes 38 and another hole 40 adapted to enable electricalwires 42 to extend from the outside of the pump 10 to the motor 22 forthe purpose of operating this motor.

The front side 34 of the wall 14 is formed so as to include a housingWall 44 having an internal cylindrical surface 46 formed therein. Thissurface is intersected by passages 48 and 50 which extend at a rightangle to the base 12 away from this base through the housing wall 44.The passage 48 extends tangentially from the surface 46. As shown inFIG. 3 of the drawing preferably these. passages 48 and 50 are parallelto one another and are located so as to be spaced so as to intersect thesurface 46 at an angle of less than 180 around the axis of the surface46 and of the shaft 30.

This construction is designed so that a flexible, elastomeric tube 52 ofsubstantially uniform diameter may be located in order to extend throughthe passage 50 so as to extend more than 180 around the axisof thesurface 46 and the shaft 30. The purpose of this particular constructionwill be made fully described hereinafter. If desired, the edge 54 of theintersection of the passage 50 and the surface 46 where the tube 52 isbent may be curved slightly so as to avoid undue wear upon this tube.

In the pump 10 the tube is periodically compressed through theutilization ofmeans for compressing this tube consisting of a rotor 56which is secured to the shaft 30 FIG. .3 is a cross-sectional view takenat line 33 of .the design and construction of pumps will realize thatother differently appearing pumps may be easily constructed on the basisof the disclosure embodied within the accompanying drawing and withinthis description so as to utilize the inventive features defined in theappended claims.

As an aid to understanding this invention it can be stated inessentially summary form that it concerns pumps or tube pumps, each ofwhich utilizes a motor in order to rotate a shaft which extends axiallywithin a discso as to rotate with respect to it and by means of spools58 which are rotatably mounted upon this rotor 56. Preferably the rotor56 includes bifurcated ends 60 which hold small axles 62 which in turnrotatably carry the spools 58. Preferably these spools 58 are formed outof a material having low friction properties such as nylon,polytetrafluoroethylene or the like, so that rotation between them andthe axles 62 may be achieved with a minimum of difiiculty. As will beseen in FIG. 2 of the drawing the spools 58 include end flanges 64 whichstraddle the tube 52 during the compression of this tube so as to aid inmaintaining the tube in a correct position against the surface 46.

gasket 76 which is disposed in'a groove 72 of the housing 5 wall 44 soas to resiliently-bear against the plate 66 and the wall 44. The plate66 also preferably includes a small oil opening 74 which is located withrespect to the interior so as to lead into the interior of thedisc-shaped satisfactory prolonged operation of the pump by minimizingthe tendency for wear with respect to the tube 52. In order to achievepreferred results of the present invention the body liquid lubricant 76should consist of an oil or an oil mixture which is substantially inertwith respect to the material from which the tube 52 is made, and whichis capable of exercising a lubricating effect with respect to this tube.It is presently preferred to utilize in the pump 16 a tube 52 formed outof a surgical grade rubber latex having comparatively thick walls and toutilize with this tube 52 castor oil since this oil does not affect thisspecific elastomeric type material as by causing swelling or the likeand is capable of exercising a lubricating function with respect to thiselastomeric material. a

As can be seen in FIG. 2 of the drawing, the body 76 is located withinthe wall 44 generally below the sealing opening 74 when the pump 111 isorientated as shown in the drawing. When, however, it is desired tomount the pump 11 at another angle than the specific angle shown withthe specific structure illustratedthis can be done pro- 7 vided the body76 is maintained within the interior of the wall 44 so that it does nottend to flow out of either of the passages 48 or 50. As an example ofthis, the pump 10 illustrated can be mounted at a right angle to theposition in which it is shown in the drawing so that the body of oil 76assumes the position having a surface level as designated by the dottedline 78 in FIG. 2 of the drawing. From a consideration of this it willbe realized that the passages 48 and 56 are spaced with respect to oneanother as. described in the preceding in order to permit the pump 10 tobe mounted in either a horizontal position as shown or in a verticalposition in which the body 76 has a surface following the line 78.

During the operation of the pump 10 relative movemerit between the tube52 and the wall 44 will normally tend to take place so as to tend tomove the tube 52 around the interior of the surface 46. A retainer 80 asindicated in FIG. 4 of the drawing is employed so as to prevent anytendency of the tube 52 to move in this manner. This retainer 80 may besecured to the housing wall .44 by means of a further screw 20 so as tocover the surface of this wall 44 remote from the wall 14 which is notcovered by the plate 66. The retainer 80 preferably includes ridges 82which fit within the passages 48 and 50 so as to resiliently engage thetube 52 without collapsing it. An efiicient holding action is achievedby utilizing on these ridges 82 small serrations 84 which extendgenerally across the passages 48 and 50. Similar serrations 84 may belocated in the bottoms of the passages 48 and 50 opposite the ridges 82.

From a consideration of the foregoing it will be realized that the pump10 shown is comparatively inexpensive to manufacture for a number ofdifferent reasons. One ofthese is that in this pump 10 the wall serves adouble purpose, while simultaneously serving as support Wall for thegear box 18 and the motor 22. In effect this wall 14 eliminates aseparate wall used for motor mounting and other purposes in other priorconstructions. It will be further realized that the base 12, the Wall 14and the wall 44 may all be formed as an integral unit by known castingor similar molding procedures with a minimum of difficulty.

The foregoing and related factors are, of course, important. The abilityof pumps such as the pump 10 to be used over prolonged periods is also,however, extremely important. With a structure formed as the pump 10 theamount of wear upon the tube used is effectively minimized, even if abody of lubricant such as the body 76 is not employed. The utilizationof a body of oil such as the body 76 is considered to materiallyincrease the ability of a pump such as the pump 10 to be operatedsatisfactorily over a prolonged period. It'is considered that this hasbeen demonstrated by tests with pumps similar to the pump 10 which havebeen utilized for vacuum purposes-in dispensing quantities of a chlorinesolution for swimming pool purposes. 7 This advantage of the use of abody of oil is achieved in the pump 10 in a very simple, effectivestructure capable of being used in various positions.

Those skilled in the art to which this invention pertains will realizethat pumps such as the pump 10 may, of course, be modified in a numberof different ways in accordance with routine engineering skill. Becauseof this present invention is to be considered as being limited only bythe appended claims forming a part of this disclosure.

I claim: 1. A pump which includes: housing means having an internaldisc-shaped cavity having ends formed therein, said cavity having anaxis and including two passages located so as to lead into the interiorof said cavity, said housing means further including slots laterallycommunicating with said passages; an elastomeric tube positioned so asto extend through each of said passages andaround more than half of andless than the entire periphery of the interior of said cavity;

means for compressing said tube so as to close said tube mounted withinthe interior of said cavity so as to be capable of being rotated aboutsaid axis, said means for compressing including rotor means rotatablymounted within said cavity and a plurality of spools rotatably mountedon said rotor means so as to be rolled along said. tube within saidcavity during rotation of said rotor means, said spools having flangesthereon, said flanges being axially spaced on said spools and beingaxially spaced from the axial ends of said cavity so that at least oneof said flanges engages with said tube when tube is compressed by saidspools;

means for rotating said means for compressing operatively associatedwith said means for compressing;

a body of oil located within said cavity so as to cover at least part ofsaid tube, said tube being inert with respect to said oil; and

a retainer carried by said housing means, said retainer includingfriction surfaces extending through said slots into engagement with saidtube.

2. A pump as defined in claim 1 wherein said friction surfaces or insaid retainer are serrated in such a direction as to resist motion ofsaid elastomeric tube through said passages.

References Cited in the file of this patent UNITED STATES PATENTS2,015,123 Pennell Sept. 24, 1935 2,428,619 Douglas Oct. 7, 19472,434,802 Jacobs Jan. 20, 1948 2,651,264 Bruckmann Sept. 8, 19532,897,767 Cordis Aug. 4, 1959 2,899,904 Becher Aug. 18, 1959 2,975,719Kaufman Mar. 21, 1961 FOREIGN PATENTS 628,785 Great Britain Sept. 5,1949

1. A PUMP WHICH INCLUDES: HOUSING MEANS HAVING AN INTERNAL DISC-SHAPEDCAVITY HAVING ENDS FORMED THEREIN, SAID CAVITY HAVING AN AXIS ANDINCLUDING TWO PASSAGES LOCATED SO AS TO LEAD INTO THE INTERIOR OF SAIDCAVITY, SAID HOUSING MEANS FURTHER INCLUDING SLOTS LATERALLYCOMMUNICATING WITH SAID PASSAGES; AN ELASTOMERIC TUBE POSITIONED SO ASTO EXTEND THROUGH EACH OF SAID PASSAGES AND AROUND MORE THAN HALF OF ANDLESS THAN THE ENTIRE PERIPHERY OF THE INTERIOR OF SAID CAVITY; MEANS FORCOMPRESSING SAID TUBE SO AS TO CLOSE SAID TUBE MOUNTED WITHIN THEINTERIOR OF SAID CAVITY SO AS TO BE CAPABLE OF BEING ROTATED ABOUT SAIDAXIS, SAID MEANS FOR COMPRESSING INCLUDING ROTOR MEANS ROTATABLY MOUNTEDWITHIN SAID CAVITY AND A PLURALITY OF SPOOLS ROTATABLY MOUNTED ON SAIDROTOR MEANS SO AS TO BE ROLLED ALONG SAID TUBE WITHIN SAID CAVITY DURINGROTATION OF SAID ROTOR MEANS, SAID SPOOLS HAVING FLANGES THEREON, SAIDFLANGES BEING AXIALLY SPACED ON SAID SPOOLS AND BEING AXIALLY SPACEDFROM THE AXIAL ENDS OF SAID CAVITY SO THAT AT LEAST ONE OF SAID FLANGESENGAGES WITH SAID TUBE WHEN TUBE IS COMPRESSED BY SAID SPOOLS; MEANS FORROTATING SAID MEANS FOR COMPRESSING OPERATIVELY ASSOCIATED WITH SAIDMEANS FOR COMPRESSING; A BODY OF OIL LOCATED WITHIN SAID CAVITY SO AS TOCOVER AT LEAST PART OF SAID TUBE, SAID TUBE BEING INERT WITH RESPECT TOSAID OIL; AND A RETAINER CARRIED BY SAID HOUSING MEANS, SAID RETAINERINCLUDING FRICTION SURFACES EXTENDING THROUGH SAID SLOTS INTO ENGAGEMENTWITH SAID TUBE.